Pressure relief panels for gas bag equipped vehicles

ABSTRACT

A pressure relief means is provided in a vehicle equipped with a gas bag restraint system for use in the event the vehicle is involved in an impact. A biased panel, in communication with the passenger compartment and the vehicle surroundings, is held down against the bias of the panel, which urges the panel open. Upon impact of the vehicle, the gas bags inflate, tending to increase the pressure in the passenger compartment. Simultaneously, the panel hinges are detonated, causing the panel to open to prevent the buildup of pressure in the passenger compartment of the vehicle.

United States Patent Radke [451 Sept. 26, 1972 [54] PRESSURE RELIEFPANELS FOR GAS BAG EQUIPPED VEHICLES [72] Inventor: Donald G. Radke,Troy, Mich.

[73] Assignee: Allied Chemical Corporation, New

York, NY.

22 Filed: Jan.ll, 1971 211 Appl.N0.:105,443

[52] U.S. Cl ..280/150 AB, 180/112, 292/D1G. 65, 49/141 [51] Int. Cl..B60r 21/08 [58] Field of Search .280/15O AB, 150 B; 296/84 K, 296/137R; 244/121, 122 AF; 180/82, 111,

112,113, 69 C; 292/D1G. 65; 49/141;

[56] References Cited UNITED STATES PATENTS 2,469,159 5/1949 Dombrowiak..49/141 X 2,188,891 1/1940 l-laltenberger ..-.180/69 C 3,495,675 2/1970l-lass et a1. ..280/150 AB 3,112,535 12/1963 Kinney ..49/31 X 3,139,7217/1964 Daubenspeck ..244/121 X 3,525,296 8/1970 Haapanen ..98/2.183,527,472 9/1970 Chute et a1. ..280/150 AB 3,561,703 2/1971 Stencel..244/122 AF 3,588,142 6/1971 Gorman ..280/150 AB PrimaryExaminerKenneth H. Betts Attorney-Marvin Bressler and Jonathan Plaut 57] ABSTRACT A pressure relief means is provided in a vehicle equippedwith a gas bag restraint system for use in the event the vehicle isinvolved in an impact. A biased panel, in communication with thepassenger compartment and the vehicle surroundings, is held down againstthe bias of the panel, which urges the panel open. Upon impact of thevehicle, the gas bags inflate, tending to increase the pressure in thepassenger compartment. Simultaneously, the panel hinges are detonated,causing the panel to open to prevent the buildup of pressure in thepassenger compartment of the vehicle.

8 Claims, 4 Drawing Figures mzmmsm m2 3.594.003

SHEET 1 UF 2 INVENTOR DONALD G. RADKE ATTORNEY PATENTEDSEPZG I972 SHEET2 OF 2 FIG-4.

SIGNAL MEANS TO DETONATOR SIGNAL MEANS -34 8- TO GAS GENERATOR 32 3,0 II IMPACT VSOOLJQSF? E INVENTOR DONALD GRADKE BY %M"VY\ M;

ATTORNEY PRESSURE RELIEF PANELS FOR GAS BAG EQUIPPED VEHICLES BACKGROUNDOF THE DISCLOSURE The instant invention is directed to a method andapparatus for preventing pressure buildup in a vehicle equipped with agas bag restraint system. More specifically, the instant invention isdirected to a method and apparatus in which a biased panel, disposed ona vehicle, in communication with the passenger compartment of a vehicleand the vehicle surroundings, is opened simultaneously with theinflation of the gas bags, upon impact of the vehicle.

The use of inflatable gas bags as a vehicle constraining means has beenproposed as a substitute for presently employed seat belts. Althoughseat belts provide excellent protection against serious injury invehicle impacts and accidents, they suffer from the defect that theiruse, by occupants of the vehicle is voluntary. Thus, they are often notused. Gas bag restraint means, on the other hand, are not voluntary. Gasbags inflate upon impact automatically.

Although gas bag restraint systems are an advance over seat belts, theysuffer from certain defects, which have not been solved by the priorart. One major defect is the passenger compartment pressure buildupwhich occurs simultaneously with the inflation of gas bags. As the bagsinflate they compress the air in the passenger compartment. Theresultant pressure buildup may cause structural damage to the interiorof the passenger compartment since passenger compartment components areusually not designed to withstand any pressure gradient. Moreover,increased pressures increases noise amplitude. Since gas bag inflationis accompanied by a loud noise, pressure elevation using some gas bagsystems may result in intolerable noise levels, unsafe to the occupantsof the vehicle.

Gas bag inflation must be very rapid in order to constrain vehicleoccupants immediately after vehicle impact. Thus, even if the vehiclewindows are partially opened, the rate of escape of high pressure airfrom the passenger compartment may not equal the rate of pressurebuildup in the passenger compartment resulting from gas bag inflationusing certain configurations. Thus, unless the windows are fully opened,the problem of increased pressure in the passenger compartment usingcertain air bag systems may be significant. Obviously, in cold climateswindows are not usually opened. Moreover, even in hot weather the everincreasing number of cars equipped with air conditioning dictate againstopened windows. Thus, until now, the problem of pressure buildup in thepassenger compartment of a vehicle has been a serious drawback to theuse of certain inflatable gas bag systems as a restraint means invehicles.

SUMMARY OF THE INVENTION The instant invention is directed to a methodand apparatus in which automatic means are provided for pressure reliefof the passenger compartment of a vehicle equipped with gas bags,simultaneously with the inflation of the gas bags following an impact ofthe vehicle.

In accordance with the instant invention, a method and apparatus isprovided for prevention of pressure buildup in the passenger compartmentof a vehicle accompanying inflation of gas bags, disposed therein,following impact. To prevent pressure buildup, a panel, in communicationwith the passenger compartment of the vehicle and the vehiclesurroundings, is disposed on the vehicle. Biased hinge means, urging thepanel toward the open position, connects the panel to the frame of thevehicle. A hold down means, also connects the panel to the frame of thevehicle. The hold down means maintains the panel in the closed positionagainst the urging of the bias means toward the open position. Detonatormeans, connected to the hinge means and in electrical communication withthe signal which initates gas bag inflation, explodes the hinge meansupon gas bag inflation, causing the panel to open and prevent pressurebuildup in the passenger compartment followingim'pact.

BRIEF DESCRIPTION OF THE DRAWINGS The instant invention may be betterunderstood by reference to the accompanying drawings of which:

FIG. 1 is a schematic representation of a vehicle equipped with thepressure relief means of the instant invention;

FIG. 2 is a schematic representation of the pressure relief means of theinstant invention disposed at another point on the vehicle;

FIG. 3 is a sectional elevation view taken along plane 3-3 of FIG. 1;and

FIG. 4 is a schematic block diagram of the electrical system of theinstant invention.

DETAILED DESCRIPTION Turning to the drawings in detail, a motor vehicle10 provided with a gas bag restraining system (not shown) is illustratedin FIG. 1. A panel 14 is disposed in the roof 12 of the vehicle 10. Asillustrated in FIG. 3, the panel 14 is connected to the roof 12 bybiased hinge means. By way of orientation, the front windshield isrepresented at 23. The biased hinge means comprises at least one biasedhinge 16. In a preferred embodiment two hinges are employed. The biasingmeans, which urges each hinges 16 toward the open position is providedby a spring 8. To counteract the spring biased hinges l6 urging thepanel 14 toward the open position, a hold down means, generallyindicated at 18, disposed at the opposite side of the panel 14, opposesthe biasing force and maintains the panel 14 in its closed position.

The hold down means 18, in a preferred embodiment, comprises a hook-likedevice 7, pivotable about a pin 4 disposed on the panel 14. Thehook-like device 7 is connected to the roof 12 of the vehicle 10 bymeans of a second pin 6 about which the hook-like device 7 is disposed.A detonator means 2, in communication with an electrical signal, whichis discussed below, is attached to the hook-like device 7 of the holddown means 18. The detonator means 2 may take the form of any one ofmany explosive charge devices known by those skilled in the art.Although only one hold down means 18 is shown in the preferredembodiment illustrated in FIG. 3, it should be appreciated that two ormore hold down means may be substituted. The number of hold down meansrequired is a function of the load bearing ability of the hook-likedevice 7 as well as the force exerted by the springs 8.

FIG. 2 illustrates an alternate preferred embodiment of the instantinvention. In this case, a motorvehicle 20 is provided with two panels24 disposed in the roof section 22 of the vehicle 20 between the backwindow 29 and the back end of the side windows 21. Although, each panel24 is smaller than the panel l4of FIG. 1, the total area of the twosymmetrically disposed panels 24, in communication with the vehiclesurroundings, is about the same as the single panel 14. The panels 24are of the same design as the panel 14. Thus, each panel 24 is providedwith at least one biased hinge means. In the preferred embodiment ofFIG. 2 two biased hinge means 26 are provided. As in the single panelembodiment, at least one hold down means 28 oppose the biased means 26to keep the panels 24 closed.

It should be appreciated that although FIGS. 1 and 2 disclose preferredembodiments which particularly define the position of the panels in thevehicle, other positions which are in communication with the passengercompartment of the vehicle and the vehicle surroundings may besubstituted. Moreover, depending on the magnitude of the gas bagsemployed, a vehicle may be provided with a panel similar to panel 14,disposed in the roof, as well as a pair of panels 24 disposed betweenthe back and side windows.

The operation of the pressure relief means will be explained byreference to FIG. 3. It should be understood that the method ofoperation of panels 24 in no way differs from the operation of panel 14,illustrated in FIG. 3, and thus the method to be described applies toany panel, in communication with the passenger compartment of thevehicle and the vehicle surroundings, no matter where situated on thevehicle.

The panel 14 is normally held in the closed position by the hold downmeans 18 which acts against the bias of the hinge means 16. Referringnow to FIG. 4, upon impact of the vehicle, an impact sensitive switch30, is closed, activating an electrical circuit 35. The circuit 35 ispowered by a voltage source 32. In a preferred embodiment, the voltagesource 32 comprises the standard 12 ,volt D.C. storage battery of thevehicle. Alternately, a separate battery may be employed. It should benoted that the electrical flow in the circuit 35 is also dependent uponthe closing of the ignition switch 34. Thus, the pressure relief systemis never operable when the vehicle engine is not running.

When the impact sensitive switch 30 is closed, following an impact ofthe operating vehicle 10, a signal 38 is transmitted to the gasgenerators provided in the vehicle. This signal 38 causes the gasgenerators, each in communication with at least one gas bag, to generategas into the gas bags, to inflate them. Simultaneously, a second signal36 is transmitted to the detonator means 2. The signal 36 causes thedetonator means 2 to explode the hook-like device 7. The panel 14 isimmediately opened, due to the urging of spring 8 in each biased hinge16. This is illustrated in FIG. 3 by the position of the panel 14 shownin dotted lines. Thus, inflation of the gas bags occurs with thepassenger compartment in communication" with the vehicle surroundings.As a result, there is no buildup in pressure in the passengercompartment, eliminating the problems associated with gas bag inflationin a closed volume.

It should be understood that the above-described preferred embodimentsof the instant invention are meant to be illustrative only. Theforegoing specification and drawings will make apparent variousmodifications which are within the scope and spirit of the instantinvention. Therefore, the scope of the instant invention should belimited only by the appended claims.

What is claimed is:

1. An assembly for prevention of pressure buildup in a vehicle equippedwith a gas bag restraint system comprising:

a. at least one panel, disposed in said vehicle, in communication withthe passenger compartment of said vehicle and the vehicle surroundings;

b. biased hinge means connecting said panel to the vehicle and urgingsaid panel toward the open position;

c. hold down means connecting said panel to the vehicle and maintainingsaid panel in the closed position against the urging of said biasedhinge means; and

d. detonator means, connected to said hold down means, for explodingsaid hold down means upon impact of said vehicle whereby said panel isopened during gas bag inflation to permit air into the passengercompartment to flow outside the compartment during inflation.

2. An assembly, as claimed in claim 1, including electrical circuitmeans in communication with said detonator means, said means comprisinga voltage source, an impact sensitive switch responsive to impact ofsaid vehicle and in electrical communication with said voltage source,whereby said detonator means is exploded by a signal generated by theclosing of said switch.

3. An assembly, as claimed in claim 1, wherein said hold down meanscomprises at least one hook-like device pivotably connected to saidpanel, said device disposed about a pin, connected to said vehicle.

4. An assembly, as claimed in claim 1, wherein said biased hinge meanscomprises at least one spring loaded hinge.

5. An assembly, as claimed in claim 1, wherein at least one of saidpanel is disposed in the roof section of said vehicle.

6. A method for prevention of pressure buildup in the passengercompartment of a vehicle due to gas bag inflation comprising the stepsof:

disposing at least one panel on said vehicle in communication with saidpassenger compartment and said vehicle surroundings;

providing said panel with a biased hinge means urging it in the openposition;

maintaining said panel closed by hold down means,

which acts against said biased hinge means; and

disconnecting said hold down means upon impact of said vehicle wherebysaid panel is disposed in the open position due to the urging of saidbiased hinge means simultaneous with inflation of said bag filling aportion of said compartment within the vehicle upon impact, to permitair in the passenger compartment to flow outside the compartment duringinflation.

7. A method, in accordance with claim 6, wherein said disconnecting ofsaid hold down means is accomplished by detonating said hold down means.

8. A method, in accordance with claim 7, wherein said detonating of saidhold down means is accomplished by transmitting a signal to saiddetonating means, disposed on said hold down means, said signalgenerated by an electrical circuit completed by closing 5 of an impactsensitive switch;

1. An assembly for prevention of pressure buildup in a vehicle equippedwith a gas bag restraint system comprising: a. at least one panel,disposed in said vehicle, in communication with the passengercompartment of said vehicle and the vehicle surroundings; b. biasedhinge means connecting said panel to the vehicle and urging said paneltoward the open position; c. hold down means connecting said panel tothe vehicle and maintaining said panel in the closed position againstthe urging of said biaSed hinge means; and d. detonator means, connectedto said hold down means, for exploding said hold down means upon impactof said vehicle whereby said panel is opened during gas bag inflation topermit air into the passenger compartment to flow outside thecompartment during inflation.
 2. An assembly, as claimed in claim 1,including electrical circuit means in communication with said detonatormeans, said means comprising a voltage source, an impact sensitiveswitch responsive to impact of said vehicle and in electricalcommunication with said voltage source, whereby said detonator means isexploded by a signal generated by the closing of said switch.
 3. Anassembly, as claimed in claim 1, wherein said hold down means comprisesat least one hook-like device pivotably connected to said panel, saiddevice disposed about a pin, connected to said vehicle.
 4. An assembly,as claimed in claim 1, wherein said biased hinge means comprises atleast one spring loaded hinge.
 5. An assembly, as claimed in claim 1,wherein at least one of said panel is disposed in the roof section ofsaid vehicle.
 6. A method for prevention of pressure buildup in thepassenger compartment of a vehicle due to gas bag inflation comprisingthe steps of: disposing at least one panel on said vehicle incommunication with said passenger compartment and said vehiclesurroundings; providing said panel with a biased hinge means urging itin the open position; maintaining said panel closed by hold down meanswhich acts against said biased hinge means; and disconnecting said holddown means upon impact of said vehicle whereby said panel is disposed inthe open position due to the urging of said biased hinge meanssimultaneous with inflation of said bag filling a portion of saidcompartment within the vehicle upon impact, to permit air in thepassenger compartment to flow outside the compartment during inflation.7. A method, in accordance with claim 6, wherein said disconnecting ofsaid hold down means is accomplished by detonating said hold down means.8. A method, in accordance with claim 7, wherein said detonating of saidhold down means is accomplished by transmitting a signal to saiddetonating means, disposed on said hold down means, said signalgenerated by an electrical circuit completed by closing of an impactsensitive switch.